Manufacture of alloys of aluminium and magnesium.



action of cutting-tools.

NiTED STATES PATENT Orricn.

LUDWIG MACH, OF JENA, GERMANY.

MANUFACTURE OF ALLOYS OF ALUMINIUM AND MAGNESIUM.

SPECIFICATION forming part of Letters Patent No. 662,951, dated December4, 1900.

Application filed July 12, 1899. Serial No. 723,559. (No specimens.)

T0 at whom it may concern.-

Be it known that I, LUDWIG MACH, a subject of the Emperor ofAustria-Hungary, residing at Jena, Empire of Germany, have invented anew and useful Process of Making Aluminium-Magnesium Alloys, of whichthe following is a specification.

This invention relates to an improvement in aluminium -magnesium alloysdiifering somewhat from those described in United States Letters Patentof February 25, 1899, Serial No. 706,848. In that specification Idescribed how magnesium exerts its influence on aluminium and aifectsits susceptibility to the action of cutting-tools. It was there statedthat magnesium added in ten to thirty parts to one hundred parts ofaluminium improves the susceptibility of the latter to the By such anaddition aluminium acquires many qualities which pure aluminium does notpossess, and this without increasing but rather decreasing its specificgravity.

This invention is another process by which the susceptibility ofaluminium to the action of cutting-tools is obtained by the use of lessmagnesium than heretofore possible and without reducing the ductility ofpure aluminium to any considerable degree. For this purpose thecomponents are melted together in such proportions that one hundredparts of the aluminium alloy will contain two to ten parts of magnesium.This alloy of aluminium and magnesium in its mechanical properties, andin particular in its workability, scarcely difiers from pure aluminium,and while it may be rolled and drawn it has the same objections as purealuminium, for it is not capable of being satisfactorily worked bycutting-tools, and, for example, it clogs up files, 85c. If'now thisalloy of only two to ten parts magnesium and one hundred parts ofaluminium is subjected to a strong compressing process byrolling,drawing, pressing, &c., the properties of the material becomequite different as contrasted with pure aluminium. The compressed newmaterial possesses very much the same qualities which can only otherwisebe obtained by essentially higher additions of magnesium-41. 6., thecompressed alloy with the smaller proportion of magnesium can beexcellently worked on by cutting-tools, &c.

In carrying out the rolling process in practice the course to be adoptedis as follows: The pieces of material are first run one, twice, or anyrequisite number of times through the rolling-mill cold. They are thenheated to from 400 to 500 centigrade, then again rolled cold once orseveral times, and so on, this treatment by alternately heating androlling the blanks being repeated over and over again until the materialhas the density and the thickness desired. The expediency of heating thealloy is accounted for by the fact that the material without being thusheated or annealed at intervals becomes brittle, whereas the heatingrestores its original tenacity.

These compressed alloys that contain from three to five parts ofmagnesium to one hundred parts of aluminium give the best results andboth as regards its cohesion and its workability may be said to beequivalent to brass,

while in regard to certain other properties--' such as tenacity, forexample-it is even superior to brass.

An aluminium and magnesium alloy containing less than two parts ofmagnesium to one hundred parts of aluminium cannot be suitably hardenedby rolling. The condensed alloy of aluminium and magnesium hereindescribed retains these good qualities even though other metals, such asantimony and arsenic, are contained in it.

Having now described my invention, what I claim as new, and desire toprotect by Letters Patent, is the following:

l. The art of producing a workable aluminium-magnesium alloy whichconsists in alloying the two metals in the proportion of one hundredparts of aluminium to not less than two nor more than ten parts ofmagnesium and then modifying the resultant alloy by mechanicalcompression, substantially as set forth.

2. The art of producing a workable aluminium-magnesium alloy whichconsists in alloying the two metals in the proportion of one hundredparts of aluminium .to not less than two nor more than ten parts ofmagnesium and then modifying the resultant alloy by compressingit andalternately heating and cooling it, substantially as set forth.

3. The art of producing a workable aluminium-magnesium alloy whichconsists in alloying the two metals in the proportion of less than ten(10) per cent. and more than two (2) per cent. of magnesium to onehundred (100) per cent. of aluminium and subsequently compressing thealloy, substaii tially as set forth. to Signed this 21st day of June,1899, at Berlin, Germany.

LUDWIG MACH. Witnesses:

WOLDEMAR HAUPT, HENRY HASPER.

